printdiv(printpage)
{
var headstr = "<html><head><title></title></head><body>";
var footstr = "</body>";
var newstr = document.all.item(printpage).innerHTML;
var oldstr = document.body.innerHTML;
document.body.innerHTML = headstr+newstr+footstr;
window.print(); 
document.body.innerHTML = oldstr;
return false;
}

<input name="b_print" type="button" class="ipt" onClick="printdiv('div_print');" value=" Print ">

<div id="div_print">

<h1 style="Color:Red">The Div content which you want to print</h1>

</div>
